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WAN – Wide Area Network. 1.4 High Level Data Link Control (HDLC). ISO/IEC 13239 High-level data link control (HDLC) procedures are designed to permit synchronous, code-transparent data transmission. Schicht 2. Data link configuration. Unbalanced (Primary zur Secondary)
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WAN – Wide Area Network 1.4 High Level Data Link Control (HDLC) • ISO/IEC 13239 • High-level data link control (HDLC) procedures are designed to permit synchronous, code-transparent data transmission. • Schicht 2 W. Schulte
Data link configuration Unbalanced (Primary zur Secondary) Balanced (Combined Station) W. Schulte
Betriebsart: • Normal Response Mode (NRM) – Aufforderungsbetriebsart – (unbalanced) • Asynchronous Response Mode (ARM) – Spontanbetrieb – (unbalanced) • AsynchronousBalanced Mode (ABM) – gleichberechtigter Spontanbetrieb – (balanced) • Hilfsbetriebsart: • Normal Disconnect Mode (NDM) – abhängiger Wartebetrieb – (unbalanced) • Asynchronous Disconnect Mode (ADM) – unabhängiger Wartebetrieb – (unbalanced/balanced) • Initialization Mode (IM) – Vorbereitungsbetrieb – (unbalanced/balanced) W. Schulte
Bild 59 HDLC Steuerfeld-Format (Modulo 8) W. Schulte
Bild 60 Steuerfeld-Format (Modulo 128) W. Schulte
Steuerfeld-Formate W. Schulte
SNRM,P RR0,P RR3,P Pri. |======| |=====| |=====| Sec. |=====| |-----|-----|-----| |-----|-----| UA,FI0,0 I1,0 I2,0F I3,0 I4,0 SNRM,P Time-out SNRM,P I0,0 Pri. |==/ /=|<------------->|======| |-----| Sec. |=====| UA,F I0,0 I1,0 I2,0P I1,2 I2,2 I3,2P Pri. |-----|-/ /-|-----| |-----|-----|-----| Sec. |-----|-----| I0,1 I1,1F W. Schulte
Zusammenfassung HDLC W. Schulte
Noch Fragen? W. Schulte